actually your wrong, you put together a set aside of money once you realize a down trend you sell of your set aside 10-20% as each 5% in value goes out when it hits base and retrends up you buy some more while its heading up, Once it reaches half the retread you sell off half of what you have bought at the lowers levels.

Its not rocket science....
You just want an instrument that went down with the whole market and still has good bones....